Wheeled carriage for artillery

ABSTRACT

A self-propelled artillery piece comprises a gun supported on a carriage having a pair of main supporting wheels, and associated with a pair of elongated carriage trails the forward ends of which are pivoted to the carriage about a pair of elongated bearing pins located in a first vertical plane which is substantially parallel to the axis of rotation of the main supporting wheels and which bearing pins are inclined obliquely outwards respectively in relation to a second vertical plane located between the bearing pins and extending orthogonal to the first vertical plane. Each carriage trail includes an auxiliary supporting wheel rearward of its associated bearing pin and adapted to be selectively displaced between a lowered ground engaging position and an elevated ground disengaged position. The bearing pins are so disposed that the carriage has the same generally horizontal inclination when the carriage trails are in their transport position, with the rearward ends of the carriage trails closely adjacent one another and the auxiliary supporting wheels in their lowered position, and when the carriage trails are in their firing position with the rearward ends of the carriage trails relatively widely separated and their auxiliary supporting wheels elevated.

United States Patent 1191 J ohnsson et al.

[ Oct. 7, 1975 WHEELED CARRIAGE FOR ARTILLERY [75] Inventors: Stig Arthur Johnsson; Arne Emil Berglund, both of Karlskoga, Sweden [73] Assignee: AB Bofors, Bofors, Sweden [22] Filed: Dec. 21, 1973 [21] Appl. No.: 427,188

[30] Foreign Application Priority Data Jan. 17, 1973 Sweden 7300600 [52] US. Cl 89/40 R; 89/40 C; 89/40 H [51] Int. Cl? F41F 23/22 [58] Field of Search 239/40 R, 40 C, 40 H [5 6] References Cited UNITED STATES PATENTS 579,261 3/1897 Driggs 89/40 R 1,084,490 1/1914 Schneider 89/40 R 1,504,504 8/1924 Randolph 89/40 R 3,315,566 4/1967 Klapdohr et al. 89/40 R FOREIGN PATENTS OR APPLICATIONS 871,877 5/1942 France .t 89/40 C Primary Examiner-Stephen C. Bentley Attorney, Agent, or FirmElliott I. Pollock [57] ABSTRACT A self-propelled artillery piece comprises a gun supported on a carriage having a pair of main supporting wheels, and associated with a pair of elongated earriage trails the forward ends of which are pivoted to the carriage about a pair of elongated bearing pins located in a first vertical plane which is substantially parallel to the axis of rotation of the main supporting wheels and which bearing pins are inclined obliquely outwards respectively in relation to a second vertical plane located between the bearing pins and extending orthogonal to the first vertical plane. Each carriage trail includes an auxiliary supporting wheel rearward of its associated bearing pin and adapted to be selectively displaced between a lowered ground engaging position and an elevated ground disengaged position. The bearing pins are so disposed that the carriage has the same generally horizontal inclination when the carriage trails are in their transport position, with the rearward ends of the carriage trails closely adjacent one another and the auxiliary supporting wheels in their lowered position, and when the carriage trails are in their firing position with the rearward ends of the carriage trails relatively widely separated and their auxiliary supporting wheels elevated.

6 Claims, 5 Drawing Figures US. Patent Oct. 7,1975 Sheet 1 of 5 3,910,157

Fig.1

US. Patent (M11975 sheath 3,910,157

Fig. 3

US. Patent Oct. 7,1975 Sheet4 0155 3,910,157

US. Patent Oct. 7,1975 Sheet 5 of5 3,910,157

Fig.5

WHEELED CARRIAGE FOR 'ARTILLERY;

The present invention relates tosan artillery piece comprising a wheeled carriage with two carriage trails, which by means of bearing pins arerotatably supported between a,turn.ed.-in, substantially horizontal transport position and aturned-out firing position, in which they rest against the ground.

The invention is primarily applicable to artillery pieces of the kind that are providedwith a drivingmachinery comprising a motor with the corresponding equipmentfor propulsion of the gun and/or for driving various functions of the gun when firing, as it is a desire to be able to place the driving machinery in front of the wheel axle, i.e. under the barrel. However, the space in front of the wheel axleis limited vertically by the ground clearance required for cross-country driving as well as by the minimum angle of elevation of the barrel when firing, i.e. the angle of depression. A circum stance which then contributes towards limiting .the space available vertically is that, in the firing position, the carriage will: have a position sloping more rearwards than when it is in the transport position. This change of the angle of inclination of the carriage, at a given angle of depression, further reduces the space available under the barrel.

In order to solve this problern',it has been proposed to make the carriage so thatit can be raised'andlowered in relation to the wheels in such a way that the carriage can be'lowered when firing, to provide for suffi cient depression of the barrel;and raised during transport, when greater ground clearance is required. However, such a design would make the gun considerably more complicated and will, of course, also be relatively expensive. i Y i The present invention offers a solution of the abovementioned problem, which does not involve any substantial complication'of the design ofthe gun, ndrany freely rotatable so-called pivot wheels. The supporting wheels arernounted in brackets 10, 11, which are rotatably supported on the carriage trails, and convertible between. the raised and lowered positions shown in FIGS. 1 snd 3 by means of hydraulic cylinders 12, 13. The left carriage trail is provided with a couplingdevice 1.4 for connecting the carriage trails together in the transport position, and there is a lunette 15 for towing the gun. a i

For lockingthe carriage trails in the firing position, supporting arms 16, 17,'are arranged, which have one end supported on the carriage and the other end guided in angular-grooves in brackets 18 and 19, respectively, fastened to the carriage trail, as indicated by the broken lines in FIG. '4.

FIG-5 shows howthe carriage trails 4, 5 are supported-on the carriage 1.-As will'be clearly noted from the" FIGURE, the bearing pins 6, 7 are arranged inclined obliquely outwards in relation to the vertical plane. In the example shown, the angle of inclination of the pins is approx. 16. Because of the inclination of the pins, the gun can be converted from travelling to firing position without any substantial change of the angle of slope of the carriage -1, i.e. the carriage retains its substantially horizontal position also in the firing position,

- as'willbe'noted from FIGS. 1 and 3. On the condition that the horizontal positionof the carriage l is main tained duringthe conversion, each carriage trail will thus move in a sloping plane, which is at right angles to thebearing pins 6 and 7.

When converting the gun from transport position to firing position, the following procedureis appliedl The coupling device 14 is'released, after which one of the supporting wheels, e.g. the left one, is raised with the aid of the cylinder 13, the load then being transferred to the right supporting wheel 8. Because'of the sloping support, the left carriage trail will then move outwards and downwards under the influence of its own weight.

significant increase in costs The carriage according to the invention is mainly characterized in .thatthe bearing pins of the carriage trails are arranged inclined obliquely outwards in relation to the vertical plane, the

angle of inclination of the bearing pins then being chosen in such a way that the carriage will have substantially the same inclined position in the firing position as in the transport position.

An embodiment of the invention will be described in more detail with reference to the attached drawings, which show a field-artillery gun provided with the car riage according to the invention.

FIGS. 1 and 2 show a side view and a plan view from above, respectively, of the gun in transport position,

FIGS. 3 and 4 are corresponding views of the gun in firing position, and

FIG. 5 shows a crosssection of the supporting device for the carriage trails along the line V\/ in FIG. 2.

The gun shown schematically in FIGS. ll-4 is provided in the ordinary way with a wheeled carriage 1, comprising two wheels 2 and 3 arranged on a common axle and two carriage trails 4 and 5. The carriage trails are rotatably supported by means of bearing pins 6, 7, between the transport position according to FIGS. 1 and 2 and the firing position according to FIGS. 3 and 4. In order to provide for self-propulsion of the gun and to facilitate the conversion of the carriage trails 4, 5 between the transport and firing positions, the trails are provided with supporting wheels 8, 9, consisting of When the carriage trail has swung out completely; it is locked with the aid of the supporting arm 17. The supporting'wheel 9- is thereafter lowered, and the procedtire described above is repeated with the right carriage trail. When also the right carriage trail has been swung out, both supporting wheels are raised, and the gun then assumes the position shown in FIGS. 3 and 4.

At the conversion from firing position to transport position, the two carriage trails are first raised slightly with the aid of the supporting wheels, so that they are not in contact with the ground. Thereafter the supporting arms 16, 17 are released, and the carriage trails are swung in simultaneously, with the supporting wheels rolling on the ground. Because of the inclination of the bearing pins 6, 7, the gun will then turn rearwards around the wheel axle in such a way that its centre of gravity will move downwards. A torque will then arise around the trail bearings 6, 7, which will help move the trails together.

From the above, it will be noted that the sloping support facilitates the conversion of the gun in both cases.

As the horizontal position of the carriage is maintained also in the firing position, the vertical space available in front of the wheel axle, where a motor 20 is positioned, will be increased. As will be clearly noted from FIG. 3, this space is limited vertically by the maxi mum angle of depression of the barrel, which for the gun shown is approx. 3. It should be obvious that this limitation of the space available for a motor at a given angle of depression will be considerably less with the embodiment shown than if the carriage in the firing position should be inclined rearwards in the same angle as the carriage trails, which is the case as regards conventional guns of this kind.

We claim:

1. An artillery piece comprising a gun supported on a carriage having a pair of main supporting wheels mounted for rotation about a common axis, a pair of elongated carriage trails extending rearwardly of said carriage and having their forward ends pivotally connected to said carriage for pivotal movement about a pair of elongated substantially vertically oriented bearing pins located on said carriage at fixed positions rearward of said pair of main supporting wheels respectively, a pair of auxiliary supporting wheels mounted on said pair of carriage trails respectively at positions rearward of said bearing pins, means for selectively displacing each of said auxiliary supported wheels between a lowered ground-engaging position below its associated carriage trail and an elevated ground-disengaged position thereby to permit the carriage trails to be selectively moved between a transport position, wherein the rearward ends of the carriage trails are located in close proximity to one another with said auxiliary supporting wheels being in their lowered ground-engaging positions for cooperation with said main supporting wheels during transport of said artillery piece, and a firing position wherein the rearward ends of said carriage trails are relatively widely separated from one another and said auxiliary supporting wheels are in their elevated ground-disengaged position so that the rearward ends of said carriage trails are in direct engagement with the ground, said elongated bearing pins both being located in a first vertical plane which is disposed behind and substantially parallel to the axis of rotation of said main supporting wheels, and said elongated bearing pins being inclined obliquely outwards respectively in relation to a second vertical plane located between said pins and extending orthogonal to said first vertical plane whereby each carriage trail moves in a generally horizontal, downwardly sloping plane relative to the ground as said carriage trail is displaced from its transport position to its firing position, the angles of inclination of said pair of bearing pins relative to said second vertical plane being so chosen that said carriage has the same generally horizontal inclination when said carriage trails are in said firing position and when said carriage trails are in said transport position.

2. The structure of claim 1 including a coupling device mounted on at least one of said carriage trails for connecting the rearward ends of said trails together in said transport position.

3. The structure of claim 1 including means for locking said carriage trails in said firing position, said locking means comprising a pair of grooved brackets mounted on said pair of carriage trails respectively, and a pair of supporting arms each of which has one end pivotally connected to said carriage and its other end located in the groove of one of said brackets for slidable movement relative to said bracket.

4. The structure of claim 1 wherein said auxiliary supporting wheels are attached to their respective carriage trails through swingable brackets, said means for selectively displacing said auxiliary wheels comprising a pair of hydraulic cylinders connected to said swingable brackets.

5. The structure of claim 1 wherein said means for selectively displacing said auxiliary supporting wheels is operative to displace said auxiliary wheels individu ally whereby, when either of said carriage trails is in its transport position and the auxiliary wheel associated with said carriage trail is then displaced to its elevated position while the other auxiliary supporting wheel is still in its lowered position, the carriage trail associated with said elevated wheel swings of its own weight about its associated inclined bearing pin toward its firing position.

6. The structure of claim 1 including means for effecting self-propulsion of said artillery piece comprising a motor mounted on said carriage below said gun at substantially the elevation of and forward of the axis of rotation of said pair of main supporting wheels. 

1. An artillery piece comprising a gun supported on a carriage having a pair of main supporting wheels mounted for rotation about a common axis, a pair of elongated carriage trails extending rearwardly of said carriage and having their forward ends pivotally connected to said carriage for pivotal movement about a pair of elongated substantially vertically oriented bearing pins located on said carriage at fixed positions rearward of said pair of main supporting wheels respectively, a pair of auxiliary supporting wheels mounted on said pair of carriage trails respectively at positions rearward of said bearing pins, means for selectively displacing each of said auxiliary supported wheels between a lowered ground-engaging position below its associated carriage trail and an elevated ground-disengaged position thereby to permit the carriage trails to be selectively moved between a transport position, wherein the rearward ends of the carriage trails are located in close proximity to one another with said auxiliary supporting wheels being in their lowered ground-engaging positions for cooperation with said main supporting wheels during transport of said artillery piece, and a firing position wherein the rearward ends of said carriage trails are relatively widely separated from one another and said auxiliary supporting wheels are in their elevated grounddisengaged position so that the rearward ends of said carriage trails are in direct engagement with the ground, said elongated bearing pins both being located in a first vertical plane which is disposed behind and substantially parallel to the axis of rotation of said main supporting wheels, and said elongated bearing pins being inclined obliquely outwards respectively in relation to a second vertical plane located between said pins and extending orthogonal to said first vertical plane whereby each carriage trail moves in a generally horizontal, downwardly sloping plane relative to the ground as said carriage trail is displaced from its transport position to its firing position, the angles of inclination of said pair of bearing pins relative to said second vertical plane being so chosen that said carriage has the same generally horizontal inclination when said carriage trails are in said firing position and when said carriage trails are in said transport position.
 2. The structure of claim 1 including a coupling device mounted on at least one of said carriage trails for connecting the rearward ends of said trails together in said transport position.
 3. The structure of claim 1 including means for locking said carriage trails in said firing position, said locking means comprising a pair of grooved brackets mounted on said pair of carriage trails respectively, and a pair of supporting arms each of which has one end pivotally connected to said carriage and its other end located in the groove of one of said brackets for Slidable movement relative to said bracket.
 4. The structure of claim 1 wherein said auxiliary supporting wheels are attached to their respective carriage trails through swingable brackets, said means for selectively displacing said auxiliary wheels comprising a pair of hydraulic cylinders connected to said swingable brackets.
 5. The structure of claim 1 wherein said means for selectively displacing said auxiliary supporting wheels is operative to displace said auxiliary wheels individually whereby, when either of said carriage trails is in its transport position and the auxiliary wheel associated with said carriage trail is then displaced to its elevated position while the other auxiliary supporting wheel is still in its lowered position, the carriage trail associated with said elevated wheel swings of its own weight about its associated inclined bearing pin toward its firing position.
 6. The structure of claim 1 including means for effecting self-propulsion of said artillery piece comprising a motor mounted on said carriage below said gun at substantially the elevation of and forward of the axis of rotation of said pair of main supporting wheels. 